The present invention is directed to improving the safety of intravenous catheters, especially to reduce the risk of accidental injury after insertion of the catheter or in discarding of the used needle-guide of the catheter.
Catheters for intravenous use typically include a needle-guide, i.e. a metal mandril, covered by a flexible plastic cannula. The needle-guide and cannula are inserted into the patient's vein, whereupon the needle-guide is removed to permit connection of the infusion drip apparatus to the cannula.
After the removal from the cannula, the sharp needle-guide remains exposed, thereby creating a risk of accidental injury to the technician or other workers in the area if the needle-guide is mishandled. The danger of transmission of infection to hospital and health service staff in this manner has become quite troublesome in recent years. This has been particularly true in the cases of diseases such as AIDS and Hepatitis B and C, for which the risks have reached distressing levels. While educational programs such as Universal Precautions and the use of rigid containers have been implemented, these have only marginally reduced the problems of accidental injuries.
Other systems for reducing the danger of accidental injury have also been proposed. For example, U.S. Pat. No. 4,832,696 proposes a system in which the needle guide is manually inserted into a protection hood after use. U.S. Pat. No. 4,747,831 suggests a system where the needle-guide can be retracted through a trigger device. Neither system is totally satisfactory, since in each case some voluntary action on the part of the technician is necessary, and therefore the danger from the exposed needle remains in the event the technician fails to undertake the necessary step.